Lina: Would always win because she would Dragon Slave the studio if she didn't. She  would also get the best prizes and the most money of all of the contestants.

Gourry: Wouldn't know how to spell any of the words, including the simple ones, and  therefore wouldn't do too terribly well.

Amelia: Would try to win in the name of justice. Would also give justice speeches every  time she had to choose a letter, therefor turning a half hour gameshow into an hour  long test of patience.

Sylphiel: Would use her divine powers to not go bankrupt or lose a turn, but would still  have problems with the spelling.

Zelgadis: Would summon the spirits of the elements to give him the maximum cash for  every time he spun the wheel. He also has a large intellect so he would win, hands  down, with a minimum of effort.

Xellos: Would become a woman to sleep with the host. Would then become a handsome  and charming man to sleep with Vanna White. The first two things would be for  the hell of it since he would simply use his Mazoku powers to make the wheel do  his bidding. However he would simply reply, "Sore Wa, Himitsu Desu" whenever  asked for a letter.

Filia: Would invoke the powers of the Fire Dragon King for knowledge, luck, and sex  appeal. Would also turn into a dragon if she lost any of the rounds and probably  trash the studio with just the transformation, let alone anything else.

Martina: Would threaten the host and the other players with the wrath of Zoamelgustar if  she isn't proclaimed the winner after the opening puzzle. If all else fails she could  simply cry and plot the demise of the host or the other players and use her  obsession to cast a powerful curse.

Phibrizo: Would threaten to crush the soul sphere of Vanna if he isn't allowed to spin,  spin, SPIN for the most money, not lose any to bankruptcy, not lose any turns for  wrong letter guesses, and then given the best, if not all of the prizes for the daily  champion.

Garv: Wouldn't do too much except curse enough to cause the studio executives to give  him whatever he wants just to make him stop cursing and swearing.

Rezo: Would summon the power of Shabrinigdo to be his eyes so that he could actually  see the puzzle. We all know what happened after that...

Copy Rezo: Would summon the demon beast Zannifar and try to outdo the original Rezo  in solving puzzles, guessing letters, spinning the wheel, and otherwise driving  everyone insane with the two large snarling dragon heads that appeared when  summoning Zannifar.

Valgarv: Now why would he waste his precious time on a game show when there is a  world to be conquored and destroyed.